Gay twin may offer answer to mystery of our sexuality

Sarah Nunn, right, says her boyfriends had more in common with her sister Rosie when the twins were growing up

When it came to boys, Rosie and Sarah saw the same thing happen again and again. “Any boyfriend instantly felt more at home with Rosie,” says Sarah, who is Rosie’s identical twin.

“She liked football, talked about boy things, played video games. They’d be like, ‘Sarah, you’re really boring. I’m going to go and play with Rosie.’ I’d get jealous that they liked her better.” But that was when Sarah discovered her one advantage. “When they tried to get romantic with Rosie she’d say, ‘That’s not me.’ Then they came back.”

Sarah Nunn and Rosie Ablewhite, 29, are a tantalising mystery to sexuality researchers. They are genetically identical and were brought up in the same household. Their nature is the same and so was their…